The present invention relates generally to heat exchangers, and more particularly, but not by way of limitation, to rod baffle heat exchangers.
Various rod baffle heat exchangers have been disclosed in the art. Several of these heat exchangers have been put into successful, practical application. With large rod baffle heat exchangers, it may be necessary to provide additional support to the baffle rods to prevent sagging of the baffle rods. This is accomplished using cross-support rods installed in the rod baffle perpendicular to the baffle rods. Another problem in large rod baffle heat exchangers is to establish a firm contact between the rods and the heat exchanger tubes while avoiding rod-to-tube tolerance build-up problems. One proposal to solve this problem was to provide rods with areas of varying cross-sections and slide the rod so that an area of the rod having a small cross-section is replaced by an area of a rod having a larger cross-section between the tubes, whereby the area of the rod with a larger cross-section is urged into firm contact with the tubes. Another proposal to solve this problem was to use rods having elliptical cross-sections; therefore, allowing easy assembly and firm engagement of the rods and tubes by simple rotation of the rods about their longitudinal axis. Another proposal is to use baffle rods which comprise circular standard rods and circular substitute rods wherein the diameter of the substitute rods differs from that of the standard rods.